This invention concerns a process and apparatus for the batch manufacturing and purifying of liquid organic peroxides resulting in increased yields, drier, purer and more active product and less pollution of the environment. More particularly, this invention relates to the recovery of liquid peroxy esters and diacyl peroxides from a batch process by countercurrent convective distillation.
Prior art batch processes for the manufacture of liquid organic peroxides, especially peroxy esters and diacyl peroxide, generally make use of chemical drying agents such as anhydrous magnesium or sodium sulfate and the like. Disadvantages of using this conventional inorganic drying agent are that the drying agent is difficult to separate from the product resulting in an impure product with a low yield. Disposing of the sulfate drying agents also creates a problem since it has become an undesirable pollutant in the environment, especially in lakes and rivers. The product also contains a high percentage of water. For example, see U.S. Pat. Nos. 3,138,627, 3,082,236, 3,117,166, 3,435,060 and 3,869,489. British Pat. No. 1,251,042 describes a process for drying a liquid organic peroxide or an organic solution of an organic peroxide that uses a microporous filter cartridge to remove suspended aqueous liquid. U.S. Pat. No. 4,075,236 describes a continuous solvent free process for the manufacture of peroxy esters. This patent differs from the instant application since it is a continuous method using a more complicated system of at least two reactors with more energy input per unit of reactor for agitation than the instant application.